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539 Ma – present. The Phanerozoic Eon (Greek: period of well-displayed life) marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, with major mass extinctions at division points.
An earthworm is a soil -dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they were in the order of Opisthopora since the male pores opened posterior to the female pores, although the ...
c. 4,300 Ma – Nectarian Era begins on Earth. c. 4,250 Ma – Earliest evidence for life, based on unusually high amounts of light isotopes of carbon, a common sign of life, found in Earth's oldest mineral deposits located in the Jack Hills of Western Australia. [4] c. 4,100 Ma – Early Imbrian Era begins on Earth.
The Lumbricidae are a family of earthworms.About 33 lumbricid species have become naturalized around the world, [1] but the bulk of the species are in the Holarctic region: from Canada (e.g. Bimastos lawrenceae on Vancouver Island) and the United States (e.g. Eisenoides carolinensis, Eisenoides lonnbergi and most Bimastos spp.) and throughout Eurasia to Japan (e.g. Eisenia japonica, E. koreana ...
Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. [4][5][6] Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen.
The climate was much more humid than during the Triassic, and as a result, the world was warm and partially tropical, [40] [41] though possibly with short colder intervals. [42] Plesiosaurs , ichthyosaurs and ammonites dominated the seas, [ 43 ] while dinosaurs, pterysaurs and other reptiles dominated the land, [ 43 ] with species such as ...
Earthworm head. Lumbricus terrestris is relatively large, pinkish to reddish-brown in colour, generally 110–200 millimetres (4.3–7.9 in) in length and about 7–10 millimetres (0.28–0.39 in) in diameter. It has around 120–170 segments, often 135–150. The body is cylindrical in the cross section, except for the broad, flattened ...
There are over 22,000 living annelid species, [6] [7] ranging in size from microscopic to the Australian giant Gippsland earthworm and Amynthas mekongianus, which can both grow up to 3 meters (9.8 ft) long [7] [8] [9] to the largest annelid, Microchaetus rappi which can grow up to 6.7 m (22 ft).